Car roof



Oct. 1, 1929. c. D. BCNSALL M 9 CAR ROOF Filed 001,- 1927 2 Sheet-Sheet 2 .f/AS QQrroxm/EX Patented Oct. 1, 1929 UNITED STATES PATENT cnnanns DAVID nonsALL, or PITTSBURGH, rnnnisyryanrn, lss cnon T0 r. n.

MURPHY COMPANY, on NEW xnns nerolv, :EENnsY ivnn' zan cenronar on or PENNSYLVANIA OAR ROOF Application filed October 8, 192?. Serial Ho. 224,790.

This invention relates to all-steel rivetedup car roofs of the type illustrated by Bonsall Patent No. 1,526,768 dated February 17, 1925, wherein the body portions of the roof sheets are arranged above and below the neutral axis and secure together to function alter the manner of the top and bottom chords of a beam; and more particularly it relates to the sub-type of roof illustrated in Bonsall Patent No. 1,481,823 dated January 29, 1924, wherein the marginal portions of the roof sheets are assembled to function after the manner of hollow box girders. The principal objects of the present invention are to increase the carrying capacity of the box girders, to vbetter coordinate the distribution of stresses in the hollow girder portion and in the body portions of .the sheet, to provide for the saving of metal without sacrifice of strength, to facilitate the manufacture and reduce the cost of the roof. The invention consists principally in increasing the depth of the hollow box girders by forming channels in one or more of the lapped portions of the sheets. It also consists informing such channels with one side wall thereof deeper than the other side wall. It also consists in forming the hollow box girders of pieces that are separate and distinct from the sheets. It also consists in the arrangements and combinations of parts hereinafterdescribed and claimed.

sections similarto Fig. 8, showing the roof In the accompanying drawings wherein like reference numerals refer to like parts wherever they occur,

Fig. 1 is a plan view of a port on of a .car roof embodying my invention, p artsbeing shown broken away to more clearly il- .lustrate the invention,

Fig. '2 is an enlarged transverse section through one-half of the roof on the line 2 -2 in Fig. 1,

Fig. 8 is alongitudinal section through the roof at the ridge on the line 83 in Fig. 1,

Figs. 4, 5, 6 and 7 are longitudinal crosssheetsof modified form; and

Fig. 8 is a longitudinal section through amodified roof construction wherein the hollow box girders are formed of flanged members that are separate and apart from the roof sheets. v 4

The roof shown in Figs. 1 to 3 of the accompanying drawings is'shown in connection with a freight car having Z-bar side plates 10 arranged with their webs horizontal, and with one flange in and extending upwardly. Metal roof'sheets 11 extend from side plate to side plate of the car and are provided at their eaves ends with depending flanges 12 that overlap the upstanding inner flanges of the side plates and are rigidly secured to the outer faces thereof by horizontal rivets18. The roof sheetsll slope downwardly on opposite sides of theridge to form a pitch or arcuate roofa nd have their-adjacent side marginal portions overlapped and rigidly secured together to form hollow box girders seamsor joints 14 that function as carlines. As shown in the drawings, the hollow box girders 14 extend from eaves to caves of the car where they are curved downwardly and merge into, the plane of the depending eaves flanges 12 oftheroof sheets.

In the roof construction illustrated in Figs. 1 to 3, inclusive, the hollow-box girders'1 l are formed by cooperating channels in the overlapped marginal .portions of the roof sheets; and the lapped portions of said sheets are rigidly secured together on opposite sides of the'hollow box girders by rows of rivets 15.

this design, the marginal portion of a-roof sheet is formed into aflatbotto n channel 16, ,whose outer side 17 is deeper than its inner side 18 and'has. atits free end an outwardly extending flange 19 parallel. with the body portion of the sheet. In this construction, the two. margins of thesheets are similar to each othera'nd are adapted for cooperation with sheets of the same form. In assembling the roof sheets, said sheets are arranged alternately in two series; -thatis, every other sheet is arranged" with its channels opening upwardly and the intermediate sheets are dis posed with their .channels opening downwardly in vertical alinement with the upwardly opening channels of the lower or first mentioned sheets. The sheets are secured together by the rivets 15 that extend through the body portion of one sheet and the marginal flange 19 of the adjacent sheet; and by reason of the one side of the channel being deeper than the other side thereof the body portions of adjacent sheets are disposed at diilerent levels or planes oltset alternately With respect to each other, thereby securing an even distribution of the metal above and below the neutral axis of the root and enabling the maximum strength of the metal to be utilized, on opposite sides of the neutral axis of the root; as more fully explained in the Bonsall patents hereinbefore mentioned. The channeling of the sheets has the effect of increasing the depth of the hollow box girder portion thereof and, in a sense, segregating such girder portion from the main body of the sheet. That is to say, the top and bottom chords of the box girder are further from the neutral axis than the body portions of the sheets are, and are subjected to greater stress; but such portions are better adapted to take care of such greater stress by reason of the stiitening and strengthening etlect due to the additional angles of the channeled mar gin. That is to say, the capacity of the sheet for resisting stresses tending to buckle it is greatly increased by giving it an angular cross section.

The root construction shown in Fig. 1 has the same cross-sectional shape as root construction shown in Fig. 8; and the roof sheets of the two constructions are assembled in the same manner. In the construction shown in Fig. 4, however, the inner side walls 18 of the side marginal channels 16 of the roof sheets are made deeper than the outer side Walls 17 of said channels, as distinguished from the sheets of Fig. 3, wherein the side marginal channels have their outer walls 17 made deeper than their inner walls 18. By the arrangement shown in Fig. 4, the channels 16, which form the upper portions of the hollow box girders, are made integral with the sheets whose bodies are disposed in the lower plane of the roof, as distinguished from the root of Fig. 3, wherein the channels 16, which form the top of the hollow box girders, are formed in the sheets, whose body portions are disposed in the upper plane of the roof.

The modified construction illustrated in Fig. 5 is similar to the root construction shown in Figs. 8 and 4:, except that the channel 16 at one side of each sheet 11 opens upwardly and the channel 16 at the opposite side of the said sheet opens downwardly. In this construction, the sheets are assembled by placing the downwardly opening side marginal channel of one sheet over the upwardly opening side marginal channel of an ad acent sheet, whereby adjacent sheets are connected by hollow box girders and have their body portions disposed at different elevations, as in Figs. 3 and 4.

In the design illustrated in Fig. 6, the

sheets are similar to the sheets shown in Fig. 5, except that the body portion of each sheet is offset along the mid line thereof, whereby each sheet has one-half 11 of its body portion disposed at one level and the other half 11 at a higher level.

The construction illustrated in Fig. 7 is similar to the construction illustrated in Fig. 6 except that the downwardly opening side marginal channel 16 of each sheet is of a width equal to the width of the upwardly oifset body portion 11 thereof, which forms the top of the box girder. With this arrangement, the tops of the box girders are disposed in the upper plane of the root and their bottom portions project below the lower plane thereof, thereby increasin the depth of the girders at the bottomonly.

In the design illustrated in Fig. 8 the sheets 11 are flat from side margin to side margin; but extra pieces comprising channels 16 arranged one abovethe other are used to form hollow box girders. Each channel 16 is provided at its side margins with laterally extending flanges 19, the bottom of the channel being flat and its one side being considerably deeper than the other. The top chan nel of the girder is a counterpart of the bottom channel but arranged with its channel opening downwardly in alinement with the upwardly opening lower channel and with its deep side in alinement with the shallow or narrow side of the lower channel. The lateral flanges 19 of the upper and lower channels 16 are riveted together with the edges of the root sheets interposed between them. As illustrated, the channels or girder members 16 are made of thicker material than the roof sheets 11; and likewise they may be made of a different metal selected with reference to its specific use.

The special advantages of this construction are that the press work is limited to the girder pieces 16 which are relatively narrow and easy and inexpensive to handle, and that the designer is afforded a very wide range of latitude as to the form of the girder members and the selection of the materials to be used therefor. It is another advantage of this construction that in making repairs a larger percentage of old parts can be used than would be practicable where roof sheets are riveted directly together.

Obviously the constructions hereinbe'fore described admit of considerable modification without departing from my invention, therefore, I do not wish to be limited to the pre" cise arrangements shown and described.

l/Vliat I claim is:

1. A car roof comprising roof sheets having their body portions disposed at one level alternating with root sheets having their body portions disposed at a diliferent level, said sheets having their adjacent marginal portions shaped and rigidly secured together said sheets being disposed at different levels and the adjacent side marginal portions of said sheets being shaped and rigidly secured together to form hollow box girders of greater depth than the distance between the levels of adjacent sheets.

4. A car roof comprising roof sheets at one elevation alternating with root sheets at a lower elevation, said roof sheets having their adjacent marginal portions shaped and rigidly secured together to form hollow box girders which are of greater depth than the distance between the upper and lower elevat-ions.

5. A car roof comprising roof sheets having their body portions disposed in spaced planes and rigidly connected along their adjacent margins by box girders whose tops and bottoms are disposed above and below the 35 upper and lower plane sheets, respectively.

6. A car roof comprising root sheets'hav ing their body portions disposed in spaced planes and rigidly connected along their adjacent margins by box girders, said box gird-. ers being of a depth which differs from the distance between said spaced planes.

7. A car roof comprising roof sheets having their body portions disposed alternately in spaced planes and rigidly connected along their adjacent. margins by box girders, the distance between the top and bottom of said girders being different from the distance between said spaced planes.

- 8. A car roof comprising a plurality of roof sheets having their adjacent margins overlapped and rigidly secured together, said roof sheets having channels formed in their overlapped margins which cooperate to form hollow box girders, the body portions of adjacent sheets being offset with relation to each other and to the top and bottom surfaces 01" said girders.

9. A car roof comprising a plurality of roof sheets, each margin of a roof sheet being formed into a channel, every other sheet being arranged with its channels opening upwardly and the intermediate sheets being disposed with their channels opening downwardly in vertical alinement with the verti- 65 cally opening channels of the first mentioned roof sheets, the adjacent body portions of nected along their adjacent margins by hol-" low box girders, each of said hollow box girders comprising reversely arranged fiatbottomed or flat-topped channels that are rigidly secured together and to the margins of adjacent sheets.

11. A car roof comprising roof sheets connected along their adjacent margins by hollow box girders, each of said hollow box girders comprising reversely arranged flat.- bottomed or fiat-topped channels that are rigidly secured together and to the margins of adjacent sheets, said channels being of heavier gage than the sheets.

12. A car roof comprising roof sheets connected along their adjacent margins by hollow box girders, each of said hollow box girders comprising reversely arranged channels that are rigidly secured together with the adjacent marginal portions of the sheets secured therebetween, said channels, having one Wall of greater depth than the other Wall whereby the sheets cooperating therewith are offset vertically with respect to each other.

13. A car roof sheet having its side marginal portions formed into flat-bottomed channels located beyond the side edges of the body of the sheet, the sides of the channels next to the body of the sheet being of equal depth with each other but of different depth from the outer sides of said channels, said outer sides having'laterally' extending horizontal flanges.

14. A car roof sheet having its side marginal portions formed into flat-bottomed channels located beyond the side edges of the body of the sheet, the sides of the channels next. to the body of the sheet being of equal depth with each other but of greater depth than the outer sides of said channels, said outer sides having laterally extending horizontal flanges.

15. A car roof sheet having its body formed into two longitudinal portions vertically offset with relation to each other and having its side marginal portions formed into channels located beyond the side edges of the body of the sheet, one wall of each channel being deeper than the other wall. thereof and the outer wall having a laterally extending horizontal flange suitable for a riveting strip.

Signed at New Kensington, Pa., this 4th day of October, 1927.

CHARLES DAVID BONSALL. 

